1. Field of the Invention
The invention relates to a housing structure; in particular, the invention relates to a housing structure with a uniform appearance.
2. Description of the Related Art
FIG. 1 is a schematic view of a conventional housing structure B (B1, B2, and B3). The housing structure B includes a lower case H1 and an upper case H2. A space is formed between the lower case H1 and the upper case H2 when they are joined. An object E, such as a hard disc drive, an optical disc drive, or the other electronic device, is received in the space of the housing structure B. A joint region J is formed at a contact point between the lower case H1 and the upper case H2 subsequent to their assembly.
Referring to FIGS. 2A–2C, FIG. 2A is a partial perspective view of the housing structure B1, and is cut away along a line T1—T1 of FIG. 1. FIG. 2B is a partial side view of FIG. 2A, and FIG. 2C is a cross-sectional view along a line X—X of FIG. 2B.
In FIG. 2A, the lower case H1 includes a side wall W1-1 and plural positioning protrusions C-1. The positioning protrusions C-1 are separately disposed on an inner wall of the side wall W1-1, and are separate from each other. The upper case H2 includes a side wall W1-2 and plural positioning plates C-2. The positioning plates C-2 are disposed on an inner wall of the side wall W1-2, and are separate from each other. A positioning hole C-3 is formed in each positioning plates C-2.
When the positioning protrusions C-1 of the lower case H1 are inserted into the positioning holes C-3 of the positioning plates C-2 of the upper case H2, the assembly of the lower case H1 and the upper case H2 is complete. The housing structure B1 is divided into an inner space IS and an outer space OS by the side walls W1-1, W1-2. The object E as shown in FIG. 1 is received in the inner space IS.
FIG. 2B shows a slit J11 presented at the joint region J1 between the side walls W1-1, W1-2. Structures inside the housing structure B1 can be seen from the joint region J1.
FIG. 2D is a schematic view of the housing structure B1 and a force F exerted thereon. When the upper case H2 is subject to the force F, the positioning plate C-2 is partially separated from the positioning protrusion C-1. Thus, the upper case H2 may accidentally separate from the lower case H1.
Referring to FIG. 3A and FIG. 3B, FIG. 3A is a partial perspective view of the housing structure B2, and is cut away along a line T1—T1 of FIG. 1. FIG. 3B is a partial side view of FIG. 3A.
In FIG. 3A, the housing structure B2 includes two side walls W2-1, W2-2 contacting each other. The side wall W2-1 is formed with a step portion M21 at its free end, and the side wall W2-2 is formed with a step portion M22 at its free end. The step portion M21 contacts the step portion M22. A joint region J2 is formed between the side walls W2-1, W2-2.
The housing structure B2 differs from the housing structure B1 in that the side walls W2-1, W2-2 are abutted by the step portions M21, M22. Since other components, such as positioning protrusions C-1 and positioning plates C-2, of housing structure B2 are the same as those of the housing structure B1, their description is omitted.
Referring to FIG. 3C and FIG. 3D, FIG. 3C is a cross-sectional view along a line Y—Y of FIG. 3B. FIG. 3D is a schematic view of the housing structure B2 being subjected to a force F.
As shown in FIG. 3C, since the side walls W2-1, W2-2 of the housing structure B2 are assembled by joining the step portions M21, M22, the structure in the inner space IS of the housing structure B2 cannot be seen via the joint region J2 from the outer space OS. When the side wall W2-2 is subjected to the force F, the side wall W2-2 cannot be positioned by the step portion M21 of the side wall W2-1. Thus, the positioning plate C-2 is partially separated from the positioning protrusion C-1, and the side wall W2-2 may be accidentally separated from the side wall W2-1.
Furthermore, since the step portion M21 of the side wall W2-1 is provided with a non-uniform cross section, a non-uniform appearance K is formed on the outer surface during injection molding as shown in FIG. 3E. Specifically, when the thickness of the product changes abruptly, as shown in FIG. 3F, the non-uniform appearance K is easily formed on the back side of the position where the abrupt change occurred. Thus, the appearance of the product suffers.
Referring to FIG. 4A and FIG. 4B, FIG. 4A is a partial perspective view of the housing structure B3, and is cut away along a line T1—T1 of FIG. 1. FIG. 4B is a partial side view of FIG. 4A.
In FIG. 4A, the housing structure B3 includes two side walls W3-1, W3-2 contacting each other. The side wall W3-1 is formed with a step portion M31 at its free end, and the side wall W3-2 is formed with a step portion M32 at its free end. The step portion M31 contacts the step portion M32. A joint region J3 is formed between the side walls W3-1, W3-2.
The housing structure B3 differs from the housing structure B2 in that the geometric structure of the combination of the step portions M31, M32 is completely reversed from that of the step portions M21, M22. Since the other components, such as the positioning protrusions C-1 and the positioning plates C-2, of the housing structure B3 are the same as those of the housing structure B1, their description is omitted.
Referring to FIG. 4C and FIG. 4D, FIG. 4C is a cross-sectional view along a line Z—Z of FIG. 4B. FIG. 4D is a schematic view of the housing structure B3 and a force F exerted thereon.
As shown in FIG. 4C, since the side walls W3-1, W3-2 of the housing structure B3 are assembled by joining the step portions M31, M32, the structure in the inner space IS of the housing structure B3 cannot be seen via the joint region J3 from the outer space OS. Additionally, the side wall W3-2 cannot be accidentally separated from the side wall W3-1 due to external force exerted by the step portions M31, M32, and the positioning protrusions C-1 and the positioning plates C-2.
However, since the step portion M32 of the side wall W3-2 is provided with a non-uniform cross section, a non-uniform appearance K is formed on the outer surface during injection molding as shown in FIG. 4D. Thus, the appearance of the product suffers.